Flotation separatins apparatus and method

ABSTRACT

A flotation separator containing a liquid circulating in a laminar flowing stream receives a mixture of intermingled fractions of a vegetable product introduced therein from a conveyor running in a direction transverse to the direction of flow and beneath the surface of said stream. Separate fractions are collected from the surface of said stream at separate locations downstream from their point of introduction, and any fraction remaining on said conveyor after exposure to said stream is collected at a point remote from said stream.

United States Patent Inventors Robert L. Hughes 207 Lane St., Modesto, Calif. 95354; Robert J. Allen, Forest Hills Apartments 238 31 Golden Ave., Battle Creek, Mich. 49017; Donald A. Barnes, 1678 W. Service Road, Modesto, Calif. 95351; Donald A. Bratsch, 136 Elliot Place, Walla Walla,

Wash. 99362 Appl. No. 658,120 Filed Aug. 3, 1967 Patented Mar. 2, 1971 FLOATATION SEPARATING APPARATUS AND METHOD 5 Claims, 7 Drawing Figs.

0.8. CI 209/156, 209/173 Int. Cl. B03b 3/30, B03d 1/00 Field of Search 209/ 156, 172, 172.5, 173, 162, 163

References Cited UNITED STATES PATENTS 6/1916 Parker 209/173 1,209,900 12/1916 Stebler 209/173 2,196,451 4/1940 Hoczer 209/173X 2,209,618 7/1940 Vogel 209/156 2,234,502 3/1941 Pixton 209/173 2,238,997 4/1941 Gaymonm. 209/173 2,283,512 5/1942 Sias 209/173 3,321,079 5/1967 Sackett... 209/390X 3,364,035 1/1968 Belk 209/173X FOREIGN PATENTS 1,079 1884 Great Britain 209/389 Primary Examiner-Frank W. Lutter Assistant Examiner-Robert Halper Att0rney--Le Fever, Quillinan & Hubbard ABSTRACT: A flotation separator containing a liquid circulating in a laminar flowing stream receives a mixture of intermingled fractions of a vegetable product introduced therein from a conveyor running in a direction transverse to the direction of flow and beneath the surface of said stream. Separate fractions are collected from the surface of said stream at separate locations downstream from their point of introduction, and any fraction remaining on said conveyor after exposure to said stream is collected at a point remote from said stream.

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sum 3 UF 3 FLOATATION SEPARATI'NG APPARATUS AND METHOD BACKGROUND or THE INVENTION This invention relates generally to the coring of vegetable products which has conventionally been accomplished through the use of aconsiderable amount of hand labor. The invention relates particularly to coring of vegetables such as green bell peppers, pimientos, or the like, wherein the meat portion of the product is a shell-like structure of a frangible nature encasing a more porous core substance at it stem end.

Conventionally, this operation has required a manual splitting or fracturing of the frangible meat shell to gain access to the core, which then required manual stripping of the core from therinner membranes of the shell to which the core is customarily attached. With produce such as peppers, pirnientos and the like,'of relatively smallsiz e, the manual operations involved considerable time and effort and rendered the coring operation of such produce relatively expensive. Furthermore,

the manual performance of these functions required relatively sharp instruments, rendering the conventional process a danger and potential hazard to the laborer,

According to the present invention, the produce to be cored is conveyed fromany suitable bin or storage supply along a belt conveyor which, near its discharge end, forms a gap with a superposed belt driven at a different speed than the first-mentioned belt conveyor. The respective belts are formed with roughened surfaces provide providing good friction on contact with the produce so that as the produce passes within the gap between 133 the opposed belts, the differential in the speed of the respective belts provides a shearing effect causing the products to fracture and in so doing to expose the core and to some extent sever the core ,frornthe inner membrane surfaces of the shell structure of the products. Theshearing action afforded the products by the differential in speed of the moving belts tends to sever, at least partly, the core from its attached meat portion since the strength of the seam attaching the core to the meat portion is less than the tensile strength of the meat portion itself.

The product mass fractured or cracked as aforesaid is then discharged from the nip of said belts into a stripper, which comprises sets of tines rotatably mounted in intermeshing relationship to stationary rods spaced apart approximately the width of an average-sized core. The tines, in rotating between said rods, push the cores between the rods and in so doing the rods restrain the movement of the attachedmeat portion to effect a complete severance of the cores from the respective meat portions of the products the gap between the respective rods being insufficient to accommodate both the cores and the partially attached meat portions.

The product mass, comprising combined, but fully severed, cores and meat portions, is passed to a flotation separator or cell providing a circulating laminar flow of a liquid havinga specific gravity greater than that of the core portions and the meat portions. Preferably, the liquidhas a specific gravity substantially equal or to or slightly more than that of the most mature fraction of the meat portions so as to enable separation of the meat portions into fractions, one consisting of portions more mature than that of the other since with products of this character, the more mature the meat portions, the highei their specific gravity. The product mass is introduced to the laminar flowing liquid at a point beneath the surface by a novel dragtype conveyor mechanism, chain driven and comprising flight or drag plates which expose the product mass to the laminar liquid flow at the bottom thereof. At a point downstream from the point of introduction of the product mass to the liquid stream, means are provided to collect the core portions which rise to the surface of the laminar stream before the meat poriportions. At a point further downstream, means are provided for collecting that fraction of the meat portions of the product mass which has a specific gravity substantially less than that of the liquid medium. The fraction of the meat portions whose specific gravity is more nearly the same as that of the liquid remains on the product input conveyor until it arrives at a veyed or distributed by any suitable mechanism to any desired location for further processing. 7

It is therefore an object of this invention to provide an improved apparatus and method for removing the cores from vegetable products.

It is a further object of the invention to provide'an apparatus and method for'decoring frangible vegetable produce with a minimum amount of hand labor or supervision.

It is a further object of the invention to decore vegetable produce through apparatusand a method which results-in producing at least three fractions of end product, i.e. the cores of the produce, the meat portions having a specific gravity substantially less than that of a predetermined value, and meat portions having a specific gravity more nearly equal to that of I said predetermined value. Further objects of the. invention, together with the features contributing theretoandthe advantages accruing therefrom,

will be apparent from the following specification when read in conjunction with the drawing wherein:

FIG. 1 is an overall view, somewhat schematic, of the apparatus in side elevation;

FIG; 2 is a plan view; partly in section, of the flotation separator element of the apparatus;

3 FIG. 3 is a sectional view taken along the line 3-3 of FIG.

FIG. 4 is a sectional view of the input conveyor for the flotation cell element taken along the line 4-4ofFlG. 3;

FIG. 5 is a sectional view of the pickup belt of the flotation separator taken along the line 5-5 of FIG. 3;

FIG. 6 is a detailed elevational view, in section, through the stripping element of the apparatus;

FIG. 7 is a sectional view through a green bell pepper disposedstem downward and illustrating the inner structure thereof with the core attached to the shell or meat portion thereof.

Referring now to the drawing, the invention is particularly adapted to process vegetable products, such as green bell pep pers, as illustrated in FIG. 7 which is a sectional view with thestem end downward taken through the middle of a typical vegetable to illustrate the structure, which includes an outer system by means of an endless conveyor belt 20 wrapped at one end about a pulley 21, on which belt the vegetables are loaded by any suitable means, not shown, the upper reach of the belt 20 traveling in a right-to-left direction as indicated by the directional arrow of FIG. 1. Superposed above the belt20 is an endless conveyor belt 25 reaching about pulleys 26,27, the belt and pulleys comprising an assembly which may be adjustably positioned to vary the gap between the lower reach of belt 25 and the upper reach of belt 20 so as to accommodate and firmly grasp products traveling on belt 20 as aforesaid. Belts 20 and 25 are driven by any suitable means, not shown, one of said belts, preferably belt 25, being driven by a variable speed motor so as to cause belt 25 to travel at a differential speed relative to belt 20. If desired, suitable backup means maybe provided for the upper reach of belt 20 and the lower reach of belt 25 was to maintain the gap between the respective belts at a predetermined and fixed spacing in accordance with the size of the vegetable products being processed. The differential in speed between that of belt 25 and that of belt 20, both of which belts are formed of a texture tending to firmly engage and grip the articles being processed, causes said articles to crack or fracture by the shearing force imparted thereto so that when the articles are discharged from the nip formed by the belts at the discharge pulleys 21, 26, the structure of the article is fractured, causing the core portion 12 to become exposed and in many instances severed from the shell or membrane portion of the article. In vegetable produce of this category, the seams interconnecting the core portion with the interior membranes of the article are weaker than the tensile strength of the membranes or meat portion of the article so that upon fracturing of the product in this manner, the stresses tend to sever the core portion from the attached shell or meat portion.

The fractured portions of the product are discharged from the discharge end of the belts 20, 25, into a stripper mechanism 30, which operates to complete the severance of the core portions from the meat portions of the products in cases where complete severance has not been accomplished by the cracking of the articles as aforesaid. The stripping mechanism, see also FIG. 6, includes a vertical chute defined by four sidewalls 31. Extending across said chute and connected at their ends in opposed sidewalls 31 are two sets of stationary rods 32, 33 arranged in parallel relation to each other to form, in effect, a grate. Disposed between the two other sidewalls 31 of the stripper chute is a rotating shaft 34, to which are secured, in a radially extending direction, sets of tines 35, the shaft 34 being rotated by any suitable means, not shown, in a counterclockwise direction as viewed in FIG. 1 so that the tines positively urge the severed or fractured portions of the products between the gate to, in effect, complete the severance of the core portions from any meat of the products to which they may be attached. The spacing between adjacent rods 35 is such as to permit passage of a core portion alone but to prevent passage of a core portion with meat attached thereto, thus, in effect, stripping the meat portion from any core portion tow to which it may be attached at this stage of processing. The provision of two sets of rods 32,33 causes the fractured portions to follow a tortuous and sinuous so course in passing through the grate structure, thereby giving assurance of the complete severance of the cores from the meat portions of the products.

The completely severed core and meat portions discharged from the stripper mechanism 30 are preferably conveyed into a washer 40, which may be of conventional construction and serves to remove all seeds from the product mass. The washer mechanism 40 should not be considered an essential feature of the instant invention but is illustrated herein to indicate the location at which it could be disposed in the event it were to be desired to remove seeds before further processing of the combined core and meat portions constituting the product mass at this stage of the process. The washer structure includes a receiving tank 41 for disposing of the seeds removed by the washing process and also includes a discharge conduit 42 through which the product mass, minus the seeds, is delivered to a flotation separator 45 for further processing.

The flotation separator 45, as can be seen in FIG. 1, 2 and 3, comprises a tank having sidewalls 46, end wall 47, bottom floor 48, and discharge end 49 which is disposed at an incline, the respective parts being joined together to constitute a leakproof structure for containing a liquid medium and suitably supported on legs or pedestals in any desired manner. FIG. 3 illustrates a quantity of liquid in the tank, which would normally be sufficient to reach the level 50, the nature of the liquid being such as may be required depending upon the type of products to be processed thereby. In the case of green bell peppers heretofore mentioned by way of example, the liquid may be ordinary water, preferably with a small amount of chlorine added thereto, since all portions of this particular vegetable product, excepting possibly the seeds, have a specific gravity less than that of water, and this is the principal determining factor in the choice of liquid to be employed.

The liquid or water contained in the tank is caused to circulate, at least through a portion of the tank, in a laminar flow by means which include a pump 55 driven by any suitable driving force or motor, not shown, the output of which pump runs to a control valve 56 which may be adjusted by a handle 57, see FIG. 5, said valve connecting the pump with a pipe 58 running to a transversely disposed header or manifold 59 in which are fitted a row of jets or nozzles 60 which discharge the liquid toward the end wall 47 of the tank, the jets 60 being disposed near the bottom floor 48 of the tank. Disposed above the header 59 and jets 60 is a substantially oval-shaped open weldment constituting a divider 61 for guiding the flow of the liquid through the tank and causing it to circulate in a substantially laminar flow. The divider 61 is suitably secured to the sidewalls 46 of the tank and provides a transverse opening extending entirely across the tank for purposes to be hereinafter described. The top surface of the divider 61 is formed with an extension 62 projecting to the left from the open portion thereof which serves to further divide the upper level liquid from the lower level liquid and thereby contribute to a smooth circulation of the liquid around the divider structure 61, 62. The upper surface of the divider structure 61, 62. The upper surface of the divider structure 61, 62 can be considered a false bottom for the tank. As can be best seen in FIG. 2, the bottom floor 48 of the tank is formed with a discharge outlet 63 communicating through a pipe 64 with the inlet to the circulating pump 55. As can be seen, operation of the pump 55 causes a jet discharge of the contained liquid through the nozzles 60 along the bottom floor 48 of the tank, which liquid circulates in a counterclockwise direction, as viewed in FIG. 3, around the divider 61 and then returns for recirculation to the pump through the outlet port 63. The liquid, in passing in a right-to-left direction over the divider 61, 62 travels in a substantially laminar flow, the velocity of the flow being controllable by the speed of the pump and also by the size of the pump outlet control as determined by setting of the control valve 56. Preferably, as can be seen in FIG. 3, the joint between the bottom wall 48 and the end wall 47 is rounded off interiorly in a concave curve to minimize the possibility of eddy currents or turbulence arising at this point and thereby contributing to the laminar flow of the liquid as aforesaid.

The combined product mass, consisting of severed cores and meat portions of the product, is introduced into the flotation separator 45 by means of a drag-type conveyor having an inlet chute or funnel 71 for receiving the product mass from the discharge conduit 42 of the washing mechanism heretofore described. The conveyor 70 comprises an upright endless tubular housing 72 defining an endless conduit, in this instance rectangular in cross section, which accommodates and through which travel a series of drag plates 73 suitably connected at opposite ends to respective links of opposed conveyor chains 75. The lower portion of the housing 70 is disposed to pass through the opening of the divider 61 heretofore described, and in so doing causes the product mass being carried by the conveyor 70 to be exposed to and placed in communication with the laminar flowing liquid passing over said divider, whereby the portions of the product mass which are substantially lighter than said liquid rise from the conveyor and float upward into the laminar flowing liquid to be picked up and collected by devices hereinafter to be described. The false bottom of the tank defined by the upper surface of the divider 61 is formed with an orifice at this point constituting a transfer port which, as can be best seen in FIG. 2, assumes the form of a triangular-shaped opening 76 which increases gradually in width in the direction of conveyor travel, the conveyor being driven to travel in a counterclockwise direction as viewed in FIG. 4. The reason for the gradually increasing size of the transfer port 76 is to prevent the entire product contained between two drag plates from immediately rising upon being exposed to the laminar flowing liquid and instead to cause the transfer of the product to take place gradually during the progress of the conveyor so as to distribute the product more evenly and minimize any disturbance to the laminar flow of the liquid passing over said transfer opening. As can best be seen in FIG. 4, the chains are drawn around sprockets 77, 78 and 79, one of which sprockets, preferably 77, is carried by a shaft suitably driven by a motor, not shown. When traversing the transfer opening 76 formed in the conveyor housing and the false bottom 61, those portions or fractions of the product mass which are substantially lighter than the circulating liquid rise into the laminar flow of the liquid and eventually float to the top surface thereof at respective points downstream from said transfer opening. A certain fraction of the product mass, generally the more mature meat portions thereof, is more nearly equal in specific gravity to the circulating liquid and therefore does not have an opportunity to rise in the short time interval it is exposed to the liquid and therefore continues to be carries carried by the conveyor 70 which, as it leaves the flotation separator tank, rises upwardly and around sprocket 78. At this point of the conveyor just beyond sprocket 78, the housing is formed with an opening through which this heavier fractioii of the product mass is dumped out of the conveyor 70 and into a discharge funnel 81 which directs this fraction onto a take-away conveyor belt 82 suitably supported or drawn around a pulley 83 driven from a source of power not shown so as to convey this heavier portion of the product mass to a desired location for further processing. Preferably, the inner wall of the conveyor housing 72 just prior to the sprocket 78 is perforated or otherwise provided with screening material which permits any liquid which maybe trapped between the conveyor drag plates to drain out of the conveyor housing and be directed back into the flotation separator tank through suitable conduits, not shown.

The portion of the product mass which rises into the laminar flowing liquid is itself separated into two fractions depending upon the relative buoyancy thereof by mechanism now to be described, the lighter fraction of this portion consisting generally of the cores and the heavier fraction of this portion consisting of meat portions of the product generally less mature than that portion of the product which remains with the conveyor and fails to rise into the laminar flowing liquid. For collecting the cores of the product,there is disposed at a point downstream (to the left) of the transfer opening 76 a collecting screen 85 which is partially submerged below the surface of the liquid and is suitably supported on the opposed sidewalls 46 of the tank in an oblique fashion. The screen 85 is submerged to point which, when considering the velocity of the liquid flow and the buoyancy of the core fraction, will interrupt and collect the cores without substantially interfering with the laminar flow of the liquid, thereby separating out of the buoyant portion of the product mass the unusable cores. in order to dispose of the cores and discharge them from the tank, there is provided a screen wiping device which comprises an endless chain 86 drawn around sprockets 87 and to which are attached a series of wiper blades 88. The sprockets 87 are driven by a suitable power source, not shown, to cause the blades 88 to traverse the screen 85 at a point slightly below the level of the liquid so as to transfer the cores collected by the screen to one side of the tank, whereat is disposed a core discharge chute 89 suitably secured to the associated sidewall 46 and having its bottom surface partially submerged for the purpose of guiding and separating the cores from the remaining meat portions during their eventual exit and discharge from the flotation separator.

Disposed further downstream (to the left) than the screen 85 is a take-away mesh belt 90 for collecting and discharging the meat portions of the product which rise to the surface of the laminar flowing liquid later than do the cores. The takeaway belt 90 spans the full width of the tank and is an endless belt drawn around rolls 91 carried by shafts disposed at opposite ends of the belt, one of which shafts is suitably driven to cause said belt to travel in a counterclockwise direction as viewed in FIG. 3. Attached in each side of the belt is a chain 92 drawn around sprockets 93 carried on the same shafts as the rolls 91 for affording positive movement to the drive of the belt. As will be seen best in FIG. 3, the submerged end of the belt 90 and its associated. roller is disposed just below the outer end of the extension 62 of the divider 61, thereby enabling belt 90 to collect thereon all portions of the floating product which was not collected by the core collecting screen 85. As can best be seen in FIG. 5, the core guiding chute 89 directs the cores onto one side of the take-away belt 90 so that rotation of the belt 90 serves to remove both cores and meat portions, but in segregated fashion, from the liquid of the flotation separator. A separator plate 94 superposed over the fake-away belt 90 maintains the cores separate from the meat portions while traveling upwards out of the flotation separator tank. The respective products are then delivered to carryaway conveyors of any suitable type by which the respective fractions of the product may be removed and distributed to any other point for such further processing as may be desired.

From the foregoing, it will be apparent that the flotation separator functions to divide the product mass into three separate fractions. One of these is a fraction which is of greatest buoyancy, consisting generally of cores which are collected by the screen 85 and eventuallydischarged by the takeaway belt 90 to their individual carry-away conveying means for eventual disposal or such other purpose as may be desired. Another fraction which is less buoyant than the cores and consisting generally of the less mature meat portions of the product is collected on the major portion of the takeaway belt 90 .to be discharged onto a separate conveyor, not shown, for further processing as may be desired. A third fraction consisting of meat portions more nearly equal in specific gravity to that of the circulating liquid remains with the drag-type conveyor until it is dumped onto its own take-away belt for further processing orintermixing with the meat portions collected by belt 90, whichever may be desired by the user of the equipment.

While there have been shown and described what are considered to be preferred embodiments of the invention, it is, of course, apparent that changes in form could be made without departing from the spirit of the invention. It is therefore intended that the invention be not limited to the particular form herein shown and described nor to anything less than the whole of the invention as hereinafter claimed.

lclaim:

l. A flotation separator for segregating and collecting separate fractions of a combined mixture of intermingled fractions of a vegetable product each having a relatively different density comprising, a tank containing a liquid of specific gravity greater at least than that of the least dense fraction of said product, means for circulating said liquid to provide a laminar flowing stream running longitudinally through said tank in a predetermined direction, conveyor means having a section each said collector means intercepting the respective fraction which surfaces before reaching the same after said respective fraction passes beneath whatever collector means, if any, are disposed closer to said conveyor section.

2. The invention according to claim 1 wherein said transfer opening in said conveyor section is of gradually increasing area in the direction of-conveyor travel.

3. The invention according to claim 1 wherein said conveyor means operates within a tubular housing, the portion of said conveyor housing leading in the direction of conveyor travel from said conveyor section being formed with an outlet for discharging any fraction of said mixture remaining in said conveyor after traversing said conveyor section.

4. A method for segregating and collecting separate fractions of a combined mixture of intermingled fractions of a vegetable product each having a relatively different density comprising, circulating a liquid having a specific gravity said mixture separated from one another in accordance with their respective densities.

5. The method according to claim 4 including the step of discharging outside of said tank and separately collecting any fraction of said mixture failing to rise-into said stream after being conveyed below the surface thereof and released for introduction therein.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No3,567,017 Dated March 2, 1971 Inventofls) Robert L Hughes et al It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the cover sheet insert [73] Assignee General Foods Corporation, White Plains N. Y. a corporation of Delaware [S4] "PLOATATION" should read FLOTATION Column 1 line 12, "it" should read its line 29 canc "provide"; line 31 cancel "133"; line 47 "portion" should read portions line 49 after "products" insert a comIr line 57 after "equal" cancel "or"; line 70, cancel "pori" Column 3 line 31 after "meat insert portions line cancel "tow"; line 38 cancel "50"; line 57 "FIG. shoul read FIGS Column 5, line 12 cancel "carries"; line before "point" insert a line 69, after "Attached" "in" should read to Signed and sealed this 7th day of December 1971 (SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Acting Commissioner of Pa1 

2. The invention according to claim 1 wherein said transfer opening in said conveyor section is of gradually increasing area in the direction of conveyor travel.
 3. The invention according to claim 1 wherein said conveyor means operates within a tubular housing, the portion of said conveyor housing leading in the direction of conveyor travel from said conveyor section being formed with an outlet for discharging any fraction of said mixture remaining in said conveyor after traversing said conveyor section.
 4. A method for segregating and collecting separate fractions of a combined mixture of intermingled fractions of a vegetable product each having a relatively different density comprising, circulating a liquid having a specific gravity greater at least than that of the least dense fraction of said product longitudinally within a tank in a laminar flowing stream, conveying said mixture beneath the surface of said stream in a direction laterally transverse to the direction of flow of said stream, releasing said mixture for introduction upwardly into said stream while said mixture is being transported beneath said surface, and collecting from the surface of said stream at respective locations downstream from the point of release of said mixture into said stream respective fractions of said mixture separated from one another in accordance with their respective densities.
 5. The method according to claim 4 including the step of discharging outside of said taNk and separately collecting any fraction of said mixture failing to rise into said stream after being conveyed below the surface thereof and released for introduction therein. 